SEGAR, Sir WILLIAM (d. 1633), Garter king-of-arms, was, according to Anstis, son of Francis Segar, who, as it is said, was a prothonotary in Holland. His mother, Ann, was daughter of Richard Sherrard. He was bred a scrivener, and held some employment under Sir Thomas Heneage [q. v.], vice-chamberlain to Queen Elizabeth, and through the interest of that statesman he gained admittance to the College of Arms, being created Portcullis pursuivant at Derby House by George Talbot, earl of Shrewsbury, 10 June 1585. In that capacity he attended the splendid festival of St. George, kept at Utrecht, 23 April 1586, by the Earl of Leicester. On 4 Jan. 1588–9 he was made Somerset herald, and in 1593 he was created Norroy king-of-arms, though his patent is dated as late as 2 June 1602 (Rymer, Fœdera, xvi. 451).

In 1603 a bill passed under the signet for advancing Segar to the office of Garter king-of-arms, in succession to Sir William Dethick [q. v.], and upon this foundation, without the authority of the great seal, he, under the appellation of ‘Rex Armorum Ordinis,’ carried the insignia of the Garter to the king of Denmark. But Dethick, soon after this disseisin, was reinstated, and on 8 Sept. he was joined in a commission, by his proper style, to invest the Duke of Würtemberg. The circumstances of this investiture led to fresh censures of his conduct, and he was deposed from his office. Segar, being conscious of the invalidity of the former signet, procured a new one, and likewise a patent under the great seal in January 1606–7 constituting him Garter king-of-arms.

In 1612 he was sent with the insignia of the order to Maurice, prince of Orange, and on 5 Nov. 1616 he was knighted at Whitehall (Metcalfe, Book of Knights, p. 168). In December 1616 he was imposed upon by Ralph Brooke, York herald, who by artifice procured him to attest and confirm armorial bearings to Gregory Brandon, the common hangman of London [see Brandon, Richard]. Both Segar and Brooke were committed prisoners to the Marshalsea, but when the iniquitous business was unravelled Segar was restored to freedom, and on 5 April 1617 the king granted him an annual addition of 10l. to his stipend (Rymer, xvii. 5). On 16 Nov. 1618 he was appointed one of the special commissioners to inquire into the condition of Lincoln's Inn Fields (ib. p. 119). He was one of the eminent persons recommended by Edmond Bolton in 1624 to be members of the projected Academy Royal, or College and Senate of Honour (Archæologia, xxxii. 146); and in 1627 he was joined in a special commission, with Dudley, lord Carleton, to invest the Prince of Orange with the insignia of the order of the Garter (Rymer, xviii. 889). He died in December 1633, and was buried in the chancel of the church at Richmond, Surrey, on the 11th of that month.

He married, first, Helen or Eleanor, daughter of Sir — Somers of Kent, knight; and secondly, Mary, daughter of Robert Browne of Evington, Herefordshire. He had a large family.

His works are: 1. An account of the festival of St. George, kept at Utrecht by the Earl of Leicester, 1586; in Stow's ‘Annales,’ ed. Howes, 1615, p. 716. 2. ‘The Booke of Honor and Armes. Wherein is discoursed the causes of Quarrell and the nature of Iniuries, with their Repulses’ [anon.], London, 1590, 4to. 3. ‘Armes of the Knightes of the Noble Order of the Garter’ [1591] (cf. Thorpe, Catalogue of Ancient Manuscripts for 1835, p. 148, where a detailed account is given of the contents of the work). 4. ‘Honor, Military and Ciuil, contained in foure bookes,’ London, 1602, fol., dedicated to the Queen. A portrait of the author, engraved by Francis Delaram, forms, in some copies, the frontispiece. Some chapters in this work are taken almost verbatim from the ‘Booke of Honor and Armes.’ The third book contains fifty-four curious and interesting chapters upon the subjects of jousts, tournaments, triumphs, and inaugurations of emperors, kings, and princes. Horace Walpole, earl of Orford, reprinted many of these chapters, at the Strawberry Hill press, in a volume entitled ‘Miscellaneous Antiquities,’ 1772, 4to (cf. Dallaway, Inquiries into the Origin and Progress of Heraldry, p. 222). 5. Verses in praise of J. Guillim's ‘Rudimentes of the Arte of Armorye,’ circ. 1610, Addit. MS. 26680. 6. ‘The Genealogie or Pedegree of … Captaine Sir William Cole of the Castell of Eneskillen,’ 1630, compiled in collaboration with William Penson, Lancaster herald. This was privately printed [London?], 1870, 4to, with additions under the certificates of Sir W. Betham and Sir J. Bernard Burke, Ulster kings-of-arms. 7. ‘R. Jacobi I Delineatio Metrica,’ being Latin verses addressed to James I and the Emperor Charles V, Royal MS. in British Museum, 12 G. ix. 8. ‘Aspidora Segariana, or the Grants, Confirmations, &c. of Sir W. Segar,’ Addit. MS. 12225: a copy collated by Simon Segar, his great-grandson. 9. ‘The Earl Marshal his Office both in Peace and War. Set down by the Special Commandment from the King's Majesty's own Mouth,’ printed in Guillim's ‘Display of Heraldry,’ ed. 1724, from the Ashmolean MS. 856, p. 431. 10. ‘Pedigree of the Family of Weston, of Sutton Place, Surrey. Addit. MS. 31890. 11. ‘The Arms and Descents of all the Kings of England from Egbert to Queen Elizabeth,’ Addit. MS. 27438. 12. ‘Baronagium Genealogicum: or the pedigrees of the English Peers, deduced from the earliest times … including as well collateral as lineal descents. Originally compiled … by Sir W. Segar, and continued to the present time by Joseph Edmondson,’ 6 vols., London, 1764–84, fol. 13. ‘Original Institvtions of the Princely Orders of Collars,’ Edinburgh, 1823, 4to, privately printed from a fine manuscript on vellum, in the library of the Faculty of Advocates; dedicated to James I.

To him has been attributed the authorship of ‘The Cities great Concern, in this Code or Question of Honour and Arms, whether Apprenteship extinguisheth Gentry?’ 1675 (Moule, Bibl. Heraldica, p. 194). The real author was Edmund Bolton [q. v.]

His great-grandson, Simon Segar (fl. 1656–1712), son and heir of Thomas Segar of St. Giles-in-the-Fields, Middlesex, was admitted a member of Gray's Inn in 1656. On 14 June 1677 he was appointed collector of all the duties of the house, except commons due to the steward. In 1674 he was appointed second butler and library keeper, and in 1675 several sums of money were paid to him for ‘setting up of the Readers' coates of armes in the Library’ (Douthwaite, Gray's Inn: its History and Associations, 1886, pp. 23, 178, 279). He published ‘Honores Anglicani; or Titles of Honour the Temporal Nobility of the English Nation (quatenus such) have had, or do now enjoy,’ London, 1712 and 1715, 8vo (MOULE, pp. 278, 279). He was also the author of ‘A Table showing the number of gentlemen admitted into the society of Gray's Inn in each year from 1521 to 1674, with an alphabetical List of the Benchers and Treasurers and other matter directly drawn from authentic sources’ (Harleian MS. 1912).